Box unstacker



Feb. 24, 1953 A. A. NEJA 2,629,503

BOX UNSTACKER Filed Dec. 6, 1948 7 Sheets-Sheet l INVENTOR.

\ AMBROSE A NEJA WNW 47 TOEA/EY '7 Sheets-Sheet 2 A. A. NEJA BOXUNSTACKER Filed Dec. 6, 1948 Feb.

on w 3 I NVEN TOR.

AMBROSE A. NEJA ATI'OAA/ey Feb. 24, 1953 A. A. NEJA 2,629,503

BOX UNSTACKER Filed Dec. 6, 1948 7 Sheets-Sheet 5 INVENTOR.

AMBROSE A. NEJA BY ATTORNEY Feb. 24, 1953 A. A. NEJA 2,629,503

I B'OX UNSTACKER Filed Dec. 6, 1948 7 Sheets-Sheet 4 A BROSE A. NEJA ask- BY M ATTORNEY Feb. 24, 1953 A. A. NEJA ,5

BOX UNSTACKER IIIIIIII'IEI a4 INVENTO. YA'MBROSE A. NEJA Patented Feb.24, 1953 UNITED STATES PATENT OFFICE BOX UN STACKER Ambrose A. Neja,Anaheim, Calif.

Application December 6, 1948, Serial No. 63,717

14 Claims. 1

This invention relates to a box unstacking apparatus.

The general object of the invention is to provide a novel apparatuswhich will operate to remove boxes from a stack and place the removedboxes upon a conveyor.

A further object of th invention is to provide a box unstacker includinnovel means for removing the lower boxes of a stack one by one.

Another object of the invention is to provide a box unstacking apparatusincluding novel holding means which serve to engage and support certainboxes of a stack while other boxes of a stack are being removed from thestack.

A. further object of the invention is to provide a box unstackingapparatus including novel pivoted holding means in the form of armswhich are mounted to move towards and from boxes in a stack to engageand hold certain boxes in the stack.

Another object of the invention is to provide a box stacking apparatusincluding novel lowerator means for lowering lower boxes of a stackwhile the upper boxes of the stack are held in stacked condition.

A further object of the invention is to provide a novel lowerator for abox stacking apparatus including novel means for engaging and loweringthe lower boxes of a stack.

A further object of the invention is to provide a box stacking apparatusincluding novel holdin means and lowerator means by means of which astack of boxes may be held and the lower boxes may be removed from thestack.

A further object of the invention is to provide a novel means foroperating a box unstacking apparatus.

Another object of the invention is to provide a box handling mechanismincluding novel means for aligning the boxes.

Other objects and advantages of the invention will be apparent from thefollowing description taken in connection with the accompanyingdrawings, wherein:

Fig. 1 is a top plan view of the unstacker in a position to receive astack of boxes.

Fig. 2 is a side elevational view with the stacker in the same positionas shown in Fig. 1.

Fig. 3 is a front view of the unstacker.

Fig. 4 is a fragmentary sectional view taken as indicated by line 44 ofFig. 1, with the unstacker in the same position as in Fig. 1.

Fig. 5 is a fragmentary sectional view taken as indicated by line 5-5 ofFig. 4.

Fig. 6 is a view similar to Fig. 5, with parts in different positionsand showing the lowerato ready to receive a stack of boxes.

- Fig. 7 is a view similar to Fig. 5, with the lowerator in itsuppermost position.

Fig. 8 is a view similar to Fig. 5, with the lowerator in position toplace an unstacked box on the outgoing conveyor.

Fig. 9 is a fragmentary view taken as indicated byline 9-9 of Fig. 4.

Fig. 10 is a schematic diagram showing the construction and operation ofthe chain raising and lowering clutch mechanism and safety featuresassociated therewith.

Fig. 11 is a fragmentary sectional view taken substantially as indicatedby line i ll l of Fig. 4.

Fig. 12 is a schematic wiring diagram of the unstacking apparatus.

Fig. 13 is a fragmentary sectional view taken on line l3-|3 of Fig. 9,and

Fig. 14 is a fragmentary enlarged side elevation showing the pivot rodand associated parts.

Referring to the drawings by reference characters, I have shown myinvention as embodied in a box unstacking apparatus which is indicatedgenerally at H]. As shown the apparatus ncludes a frame ll, feed chainsl2, elevating chains I3, a lowerator apparatus M, a lowerator drivingmechanism [5, a holding mechanism I6 for holding a stack of boxes,controlling means I! for controlling the holding mechanism I6, anddelivery chains I8. The boxes shown at B consist of ends B bottoms B apair of side boards B and top cleats B The frame I l comprises a pair oflongitudinal, parallel floor support angles 20 and 2|, adapted to befastened to a floor 22, which has a well 22' therein.

Forward vertical support angles 23 and 24 and longer rear verticalsupport angles 25 and 2G serve to support most of the unstackingapparatus. Supports 23 and 25, 24 and 26 are connected at their tops byangles 21 and 28 and at their bases by angles 29 and 30 and are fixed asat 3i to the floor support angles 20 and 2|.

The bases of the forward supports 23 and 24 are further secured inspaced relation by angles 32 and 33, and the rear supports 25 and 26 aresecured by an angle 34. Support members 35 and 36 serve to brace thecenter of the apparatus and an angle 37 braces the upper portion of therear supports 25 and 26. Th angles which compose the frame may besecured to one another as by welding. The entire vertical portion of theframe is disposed at a slight angle to the Vertical as shown in Fig. 4for a purpose to be later described.

At the outer forward ends of the floor members 23 and 2I I arrange across member 40 supported from the floor members 29 and 2I by angles IIand 42. The cross member 49 acts as a forward support for longitudinalbearing supports 43 and 44 (Fig. 3), which make a slight jog downward asat 44' (Fig. 4) and continue rearwardly to the rear end of the well 22'in which the unstacker is placed. The rearward end of the supports 43and 44 is-supported by the angle 34.

The incoming chains I2 consist of a pair of chains 45 and 48 which mayextend out in channels 41 in the floor 22 for any desired distance fromth unstacker and serve to deliver stacks of boxes to the machine. Theinner ends of the chains 45 and 45 terminate at sprockets 48 and 49,mounted on a shaft 50 which is journaled in bearing blocks 5| and 52fixed to the bearing supports 43 and 44.

Adjacent to bearing block 52 and fixed to the shaft 55, I have arrangeda sprocket 55, adapted to receive a drive .ch ain 5.6, driven by asprocket 51 mounted on a shaft 53, which is in turn journaled in abearing block 59 on hearing support .44, and a bearing block 99, fixedto an extension angle fiI, arranged between the upright 24 and the crossmember 40.

The outer end of the shaft 53 carries a sprocket 65, adapted to receivea primary drive chain 66 connected to a. sprocket 6], which is driven bya shaft 63 from a motor 69 through a gear box Ill. The motor 69 issupported on a suitable support I I, composed of angles which may befixed to the frame floor member 22 as by welding.

Thus it may be seen that through the motor 69, chains 65 and 56, withtheir associated sprockets, incoming floor chains 45 and 46 may bedriven to bring a stack of boxes into the machine.

It is customary to stack fruit boxes such as are used for oranges,lemons, grapefruit, et cetera, in stacks of from 6 to 9 boxes. Thestacked boxes are permitted to stand for several hours beforeprocessing. The chains 45 and 4G serve to bring the stacks of boxes fromthe place of storage.

Th supplemental elevating chains, indicated generally at I3, consist ofa. pair of chains "I5 and I5, supported at their outer end by SprocketsTI and -18, mounted on a shaft I9 journaled in bearing blocks-8B and BI,mounted, respectively, on the bearing support angles 43 and 44.

The shaft 'I 9 also supports the pivotal end of chain support frames,indicated generally at 85 (Fig. 4). The frames 85 are supported byhearing plates 85 and 81. Each frame 95 is composed of two sidemembers.Each side member consists of an upper angle member 88 and a lower anglemember 89. At their free ends the angle members 8'8 and 89 engage abearing plate 90 in which is journaled a shaft 9|, whichsupportssprockets 92 which, in turn rotatably support the inner ends ofthe chains I5 and I6. The side members of the frame 85 are held at theirinner ends in Spaced relation by a cross angle 93. Roller stops 94,fixed to the plates 9!], limit the inward movement of the stack.

The frame 95 is adapted to be moved into an upper and lower position andis retained in these positions by the action of cam members 95, as shownin Figs. 4 and 11. The cams 95 are eccentrically supported on a shaft 96which is journaled in bearing blocks 91 and 98, fixed to bearing supportmembers 43 and 44. The cams 95 are notched as at IIIU and HM, thesenotches being adapted to receive rollers I02, fixed to the upper frameangles 88 by a shaft I03, the outer end of which is journaled in a sideplate I I14. Thus it may be seen by a rotation of cams in a manner to belater described, the frame 85, together with the chains I5 and I8, maybe raised and lowered to position as shown by Figs. 5 and 6.

The drive for the elevating chains I3 consists of a motor I06 and a gearbox III'I, mounted on the support II. Through the gear box IU'I themotor I06 drives a shaft I06 and a sprocket I09 (Fig. 2) The sprocketI09 receives a chain III] which passes over a sprocket IIII on a shaftIII. The shaft II I is journaled in bearing blocks H2 and I I3, fixed tobearing supports 43 and 44.

Adjacent to the bearing block I I3, the shaft I I I carries a sprocketII4 which supports and drives a chain H5. The chain Il5 engages asprocket I I6, fixedto the shaft SI, which, :as has been previouslymentioned, supports th inner ends of chains I3.

Another sprocket I20, also mounted on the shaft III, is engaged byclutch drive chain vI2I. The chain I2I also engages a sprocket I22 onshaft 96 and is adapted to drive the rotating portion I23 of a clutch,the fixed portion of which is indicated at I24.

An angle support I2'I (Fig. 10), fixed between the cross member 43 andthe bottom frame member 33, supports a bearing block I28 whichsupports ashaft I23. The shaft I28 sup-ports levers I29 and I30, so placed asto'be rocked by a stack of incoming boxes. The lever I29, throughextension I,3I, Figs. 1 and 2, is adapted to operate an electricalswitch I32, the operation of which will be later described.

The lever I39 includes an arm I33 (Fig. 10), connected to a rod I34.Therod I34 is connected. to a cross arm I35 mounted on a pivot I34. Thecross arm includes a clutch stopping member I33 rigid on the arm I35.When the cross arm is rocked it releases the member I36 from engagementwith the clutch I24. The cross arm I35 at its upper end is connected toa rod I3'I which is in turn connected to a lever I38 which has an armI39 thereon. The arm I39 is a clutch stopping member. This member I39 ispositioned to stop the rotation of the shaft after a half turn has beenmade.

To insure this half rotation, I have arranged on the shaft 96, adjacentto the bearing block 9.8, an arm I42 (Fig. ,4) which c ries a pair ofrollers I43 and I44 at its outer end, These, rollers 643 and I44 areadapted to engage in a notch I45 in an arm I46, pivotally supported asat M! to a bearing block I48 fixed to the bearing support angle 44.

The notch I45 is held in engagement with either roller I43 or I44 by atension spring I49, connected atone end to the outer end of the arm I43and at the other end fixed to the bearing support 44 at its downward jog45.

The lowerator apparatus, indicated generally at I4, consists of a pairof opposed plates I55 arranged on each side of the aparatus between theupright support members 23 and '25, 24 and 26, respectively. Inasmuch asthe two sides of the lowerator mechanism are identical except for beingrights and lefts, only one set of reference numerals will be used, thusavoiding unnecessary confusion. For simplicity, the lowerator associatedwith left plate I55 has been shown in detail and will be dscribed,

The plates I55 rotatably support at their four corners rollers I56 whichare adapted to engage and roll against vertical guide shafts I51 and I58fixed between said supports 35 and 38 at their tops and lower angles 29and 30 at their bottoms. The plates are movable from their upperposition as shown in Fig. 7 to the extreme lower position as shown inFig. 6 by means to be later described.

A shaft I60, journaled in bearing blocks I6I and I62 fixed to the platesI55 as at I63, supports a pair of stack supporting arms I64 and IE5. Theouter ends of the arms are connected by a stack engaging member I66 asby welding. A spring rod I61 pivotally mounted as at I68 on the stackengaging member I66 passes through the plate I55 and is surrounded by acompression spring I69. The inner end of the spring I69 engages theplate I55 and the outer end engages a flange I on the spring rod I61,normally urging the stack engaging member I66 to the position shown inFig. 5.

At the outer end of the shaft I60 I have arranged a crank "I (Fig. 4)which rotatably supports a roller I12 which, upon upward movement of theplate I55, is adapted to engage a cam lever I15, thus moving the arm "Iand the stack engaging member I66 to the position as shown by Fig. '7 toengage the lower end of a stack of boxes B.

The cam lever I is pivotally supported at I16 to a support angle I11fixed to the frame member 26. Angle I11 also suports a spring backingplate 518, the rearward side of which pivotally supports, as at I19, anemergency switch actuating lever I80 which has a protruding switchactuating arm I3I thereon. A switch actuating rod I82 is slidablymounted in the plate I18, having its outer end fixed to the lever I80and its inner end rotatably supported as at I83 to the cam lever I15,and is surrounded by a compression spring I84. A switch I85 is fixed tothe member 25. Thus it may be seen that if the box engaging arm I66 isunable to engage the lower edge of a stack when the roller I12 strikesthe cam lever I15, the rod I82 will be moved, thus moving the lever I80and the arm I8I, opening the switch I85 and stopping the machine in amanner to be later described in detail.

It is often necessary to align the individual boxes in the stack beforethey are unstacked. To accomplish this action I have arranged arms I90pivotally supported on the shaft I60 with an extension I9I at theirlower end. The extension I9I is engaged by a compression spring I92,arranged between bosses on the plate I55 and the extension arm I9I,which normally urges the arm I90 to the position shown in Fig. 6. A boxengaging member I93 is fixed to the upper end of the arms I90 as bywelding.

A roller support member I94 is fixed on the rear of the arm I90 androtatably supports a roller I95. Upon upward movement of the plate I55the roller I95 is adapted to engage a cam lever I96 which is pivotallysupported at I91 to an angle frame I96 which in turn is fixed to the midsupport member 36. A compression spring I99, arranged between the camlever I96 and the angle frame I98, normally urges the cam lever I96 tothe position shown in Fig. 5, the lever I96 being held against furtherextension by a limit rod 200.

Thus it may be seen that upon upward movement of the plate I55 theroller I95 will engage the lever I96, moving the arm I90 to the positionshown in Fig. '7, thus aligning the lower box in the stack. If, assometimes happens, the box being aligned is wider than normal, the

springs I99 will be compressed, still aligning the box.

The lowerator driving mechanism I5 consists of a motor 205, connected bymeans of a gear box 206 to a shaft 201, which supports a sprocket 208and drives a chain 209. The chain drives a sprocket 2I0 mounted on ashaft 2i I. The shaft 2II is journaled in bearing blocks 2I2 and 2I3(Fig. 2), fixed to the rear vertical support frame members 25 and 26.Fixed adjacent to the outer ends of the shaft 2| I, I arrange a pair ofrotating arms 2I4 and 2I5, the outer ends of which rotatably supportchain rollers 2I6 and. 2". The rollers 2I6 and 2I1 engage loweratorchains 2I8 and 2I9. One end of each of the chains 2I8 and 2I9 is fixedas at 220 to arms 224 which are fastened at their lower end to theplates I55 at 222. A spacer 223 (Fig. 5), arranged between the plate I55and the arm 22I, braces the arm 22 I. Each of the chains 2I8 and. 2I9extends upwardly and passes over sprockets 225, mounted on a shaft 226journaled in bearing blocks 221 fixed to the upper side of the mid angleframe members 35 and 36.

The chains 2I8 and 2I9 continue rearward over pulleys 228 and 229 on theshaft 2 and around rollers 2 I6 and 2I1 and have their inner endssecured as at 230 to the mid angle members 35 and 36. Thus upon rotationof the arms 214 and 2I5 the chains 2I8 and 2 I9 will be moved in such amanner as to raise and lower the plates I55 as previously mentioned.

The means indicated generally at I6 for secur ing and holding a stack ofboxes in a raised position includes a pair of angle securing members 235and 236 arranged between the forward upright frame members 23 and 24.These members 235 and 236 each have a face A to engage the outer face ofa box and a face A to engage the ends of a box. The faces A may be linedwith rubber or a like substance, as shown at 231, for greater grippingeffect.

The members 235 and 236 are rotatably supported as at 238 by arms 239and 240 (see Fig. 2) The inner ends of the arms 239 and 240 arerotatably fixed to bearings 24I which have substantially vertical axes.Each bearing 24I is in turn rotatably mounted on a shaft 242 which has ahorizontal axis. Thus a substantially universal mounting is provided forthe arms 239 and 240.

The upper ends of the angles 235 and 236 are supported as at 243 by arod 244 (see Fig. 4), which is slidably mounted in a boss 245 protrudingfrom an angle 246. The use of the rod 244 will be later described.Springs 241 and 248 normally hold the rod 244 in the position shown inFig. 4. A pivot rod 250 (Fig. 2) extends downwardly through each bearingI at the upper ends of the arms 239 and 240. The rods 250 terminate atthe lower end in a boss 25I mounted on a spacer 25I' fixed to an anglemember 252' secured to an extension arm 252 which latter extendsdownwardly from the bearing 24I. The rod 259 rotatably supports one endof a brace 253, the other end of which is fixed to the arms 239 and 240.

Thus it may be seen that the angle securing members 239 and 240 areadapted to be moved either horizontally or vertically about the verticalshaft 250 and the horizontal shaft 242 to the desired position. It willalso be seen that a downward motion of the seeming members 239 and 240will also bring them rearwardly and in close contact with a stack ofboxes. retaining 7. them .in :a raised position, the'purpose of whichwill be later described.

.Inbrder to provide .for the -lateral movement of the .entire stacksecuring :apparatus l8 as a unit to xcompensatefor'any misalignment ofthe boxes in the stack, I.have arranged a series of flexible pivots tosupport a floating backing plate 260. Pivotally supported'as at 26|(Fig. 2) to the upper :cross angle member 131, I have arranged arms 252,the lower ends of which are pivotally mountedto the angle 235 whichforms the'upper stiffening member for the plate 250. These arms 252 arein vertical spaced relationship, with I only one shown. Pivotallysupported by the horizontal edge of angle 246 as at 232, I arrange asecond set of braces 26.3 and 2E4, the outer ends of which are pivotallymounted as at- :255 to the central portion of the upper angle framememberszi and 28. Another set of braces -ZSE and Z-S-T (below the braces:233 -and254) are pivoted at 282" to a brace member 268 and at the lowerend of plate 23%) and toblocl: fixed to the upper surfaces of midangle-members 235 and 236. This movable plate 269 further includesvertical brace angles 270 andill and .a lower central brace 2'52.Between the members 226 and '21! I have arranged a shaftZlI-i, the useof which will be later described.

From the upper ends of the vertical franc members-25 and 2G, I havearranged braces 215 and 216 which support a fixed guide plate 27?. As afurther guide I havearranged tubular supports 218 and 219 which extendupward from the horizontal frame members 2? .and 28 and tubular members288 and 28! upward from the braces 23-5. A horizontal tubular member2532, as shown in Fig. 3, connects the tops of these brace members.

Referring now to the mechanism indicated generally at IT for controllingthe securing mechanism: The shaft 25! acts as a central control fromwhich a pair of cams 235 and 285 (Fig. 4) operate. These cams areadapted to engage rollers 2B? journaled in brackets 283, which are inturn fixed to the extension arm 252 depending from the shaft 242 tocause the securing means to move upwardly. The cams 235 and 285 are alsoadapted to engage a pair of rollers 2852 (Figs. 2 and .4) journaled inbrackets 29.3 which are in turn fixed to upper extension arms 23L Thearms 29| extend rearwardly from the shaft 252 and are fixed to thejournal of the boss 24 l. Thus it may be seen that engagement of therollers 235 and 286 with the rollers 28e'will cause the securing meansHi .to move inwardly to engage and hold a stack of boxes.

Should the lower box in a stack .being engaged be slightly wider thannormal, I have provided a compression spring 295, positioned between theupper rearward end of the extension arm 29| and the inside center of aU-shaped support 298. The support 238 has its inner lower end fastenedas by welding to the lower extension arm 252. A rod 291 retains thespring 295 in the desired position.

Shaft 2|| also carries a pair of switch cams 300 and 38: (Fig. 4),adapted to operate switches 30.2 and 393, the purpose of which will belater described. The switches 332 and 303 are mounted on a bracket 364which is fixed to the upright frame member 26.

To adjust the securing apparatus l6 so that the bottom box of a stack ofboxes is at the center of the unstacker, I have provided an aligningmechanism consisting of a pair of adjusting cams 335 and 130.6 (FigS...9and 13) fixed to the shaft 2| The cams 305 and .396 areadapted to nga aprotrudingtab 30?, carrying a cam 306and fixed to a bracket 308, whichis in turn fastened to the cross member 212 of the floating backing.plate 25.). As the stack of boxes is -unstacked, thisaligning-mechanism adjusts each lowermost box to acentral position inthe machine, thus allowin for much misalignment in th -original stack.

To provide for the outward movement of the securing angles 235 and 238after the last box of the stack has left the machine and to clear theway for anew stack, I have mounted a roller bracket 3 IE (Figs.-4 and 3)on the shaft 2| I. The bracket supports a roller 3 which may engageadepending section3|2 of an actuating lever 3 I3. The lever 3 I3 ispivotally fixed as at? 4 to a chain uide 3| 5.

The chain guide :3|5, through a boss 3|6, is attached to a collar 3Hfixedon the shaft 242. The chain guide 3|5 has a channel 3|8 throughwhich a chain 3 [9 passes. Each end of the chain 3|9 is fixed to an arm323. The arms 320 are fixed to the arms 23!! and 249 of the securingapparatus It. A rod 32| slidably arranged between the ends of the arms32!] and vcarrying compression springs 322 terminated against bosses 323serves to return the securing angles 2.35 and 236 to their normal.closed position. Thus it may be seen that upon engagement of the roller3| with the member 3 |2 and the lever M3 the chain guide 3|5 will beturned, tightening the chain 3|9 and opening the securing angles 235 and236 to the position shown in Fig. 1.

The shaft Elli arranged between the vertical plate members 210 and 2Hcarries a collar 325, from which depends a switch lever 326 (Figs. 4, 9and '10) The lower end of this switch lever is bent back against itselfto form a box engaging section 321.

A switch lever 336, also fixed to one end of the shaft 21.3, is adaptedto operate a switch 334 mounted on oneof the backing plate stiffeningmembers 2' when the box engaging section 32-? of the arm 326 isdepressed by the lower box of a-stack. The purpose of this switch 331will be later described.

Another lever 335, mounted on the shaft 213 adjacent to the arm 32$, hasits upper end in position to contact a stop extension member 336 on theforward side of the lever 3|-3. A tension spring 331, fxed between thelever :33? and the arm 3|3, normally urges the two together. A secondtension spring 338, fixed between the lever 335 and a brace 339,normally urges the lever 329 to the position shown by Fig. 4. The brace339 is fixed as by welding :to'the cross stiffening member 2T2 of theplate 269.

Thus it may be seen that as long as the lever 32% is held in a depressedposition, the lever 3|3 and its depending top 3|2 will be held out ofengagement with the roller 3| I,, thus leaving the securing angles 2'35and 233 in their inward position to engage the lower box of a stack.

As a timing mechanism to vdelay the operationof the clutch i 24 and thesubsequent lowering of the chains I3, I have provided a stop lever 342(Fig. 10), adapted to engage a roller 343 journaled in one end of acrank 344 .pivotally secured to the brace 2-90 as at 345. The outer endof the crank 344 is fastened .to a pushrod 346 at 347. The lower end ofthe push rod 346 is fixed as at 348 to a lever 349 fixed to a shaft 35.0journaled in a bearing block 35I fixed to the upright frame member 25.

The shaft 356 carries a two-way crank 352. The upper end of the crank352 engages a lock member 353 of a lever 354, pivotally mounted on ashaft 355 which is journaled in bracket 356 secured to the upright framemember 25. The outer end of the lever 354 carries a roller 35'! which isadapted to be engaged by a cam plate 358 (Fig. 2) fixed to the pivotalshafts supporting two of the rollers I56 on the plate I55 as at 359. Thelower end of the crank 352 is connected by means of a rod 366 to thelever I38 of the clutch control mechanism as at 36!. Tension springs 362and 363 adjacent the clutch mechanism normally urge this mechanism tothe position shown by the solid line of Fig. 10.

Thus it may be seen that even though the lever 342 is moved out ofengagement with the roller 343, the clutch mechanism I24 cannot operateuntil the plate I55 has descended far enough to cause the cam plate 358to engage the roller 35! to unlock the lock member 353, allow ing theclutch mechanism to operate.

As a safety measure, levers 365 and 366 (Fig. 4) connected at the outerends by a cross mem ber 36? and pivotally connected as at 368 to bearingblocks 369 fixed to the bearing angle member 46, have been placed insuch a manner as to intercept an outgoing box. An L-shaped arm 316,dependent from the lower end of the lever 366, engages one end of aspring 35!. The other end of the spring is fastened to a switch 312which is fixed to the bearing support 44. The operation of the switch312 will be later described.

The outgoing conveyor indicated generally at I8 includes a pair ofchains 383 and 38!, carried by sprockets 382 and 383 fixed to the shaftIII and; driven by the motor I66. The chains are also carried bysprockets 384 and 365, rotatably supported on the outer ends of theshaft 96. The upper reach of the chains 386 and 38I is somewhat lowerthan the upper reach of the incoming chains I2 or the supplemental chainI3, as shown in Fig. 4. The upper portion of the chains 386 and 38I issupported by chain guides 386 and 381, fixed by means of brackets 388(Fig. 2) to the bearing support members 43 and 44. Chain guides 369 and396, fixed to the bearing support members 43 and 44, support the lowertravel of the chains 386 and 38L Cam members 36!, fixed to the outeredges of the supports, serve to cam the levers I65 from beneath thelowerbox, as will be later described. :An outgoing belt type conveyor365- may be used to-convey the individual boxes from the machine. 7 r

-- -Mounted on the bracket364, I provide a third switch 466, adapted tobe actuated by a cam 46! on the shaft 2H. This switch 466 is connectedin line with a limit switch 465. This limit switch 465 is operable by apressure lever 466 above the chains 380 and 38I and pivotally mounted bymeans of levers 461 and 468 to the floor angle 26. A spring 469 normallyurges the pressure lever 466 to the position shown in Figs. 1 and 2.

As a safety feature I have provided vertical rods 4I2 (Fig. 4), fixedbetween the base angles 29 and 30 and the top frame members 21 and 28.The rods 4I2 support three box engaging levers M3 in such position as toengage the lower three boxes of a stack. Adjacent to the lower end ofthe rods 4I2 I provide a switch lever 4 I4, adapted to actuate a switch4I5 mounted on the floor frame member 2|. Thus it may be seenthat a 10box too wide or too badly out of line to enter the machine will tripthis switch and stop the operation of the entire machine.

In operation, and referring particularly to the wiring diagram of Fig.12, a stack. of boxes from 6 to 9 high i brought into the apparatus onthe feed conveyor I2. The lowermost box strikes the switch lever I 36which causes the clutch I24 to operate, thus raising the chains I3 anddepressing lever I23, engaging switch I32 to stop the motor 63. Thestack continues into the machine until the roller stops 64 are engaged.At this point the second box from the bottom of the stack engages theportion 321 of the lever 326, closing the switch 331 and starting themotor 265, which continues in'operation until the last box clearsthelever 326, opening the switch 33 I.

The depressing of lever 326 also moves the arm 335 from engagement withthe stop 336, allowing the tab 3 I 2 to disengage from the roller 3I I,causing the securing angles 235 and 236 to engage the second box fromthe bottom of the stack. The parts are so arranged that the faces Afirst engage the outer face of the box and pull the box towards thefloating plate 266 to align the en gaged box. Thereafter furthermovement of the member 235 and the member 236 causes the faces A andalso the faces A to tightly hold the box which they engage. The cams 285and 286 engage the rollers 289, further increasing the pressure on thesecuring apparatus I6. At the time this securing operation takes place,the plates I 55 travel downward to the position shown in Fig. 6,allowing the cam plate 358 to engage the roller 351 and, by means of thelinkage previously described, lower the chains I3. The lowermost box isthus deposited on the outgoing chains I8 to be conveyed from themachine.

The plates I55 continue upwardly until the outward extension of the armsI64 and the cross members I66 engage the bottom of the lowermost box ofthe stack, raising it slightly and thus aiding the release of thesecuring apparatus I6, which is completely accomplished by engagement ofthe cams 285 and 286 with the rollers 281. The stack is positioned inthe center of the machine at this time. This position is illustrated byFig, '7.

The plates I55 then continue downwardly, car'- rying the complete stack.At a point near the bottom of the travel, the holding apparatus engagesthe next to the bottom box to hold that box and those boxes above itwhile the bottom box continue downwardly to be deposited on the outgoingconveyor I8, the arms I65 being carried out of the path by the cams 39LThis operation continues until, all the boxes have been unstacked,whereupon the securing angle 235 and 236 spread apart and the machinecomes to rest pending the arrival of a new stack into the unstacker.

Should the boxes fail to clear the machine at a suflicient speed to keepthe conveyor 395 full, the switch 465 and the switch 406 will be bothopened, causing the machine to be stopped in the position shown by Fig.8.

The switch 3I2 is adapted to stop the motor I06 and the outgoingconveyor should a box be broken or be too low to clear the machine.

In the foregoing description I refer to my invention as employed in amanner wherein single boxes are removed one by one from the bottom of astack and in which the holding means engages the next to the bottom boxof the stack. It will be understood, however, that this holding meansmay engage the third box from the bot- 1 l, tomof; the stacker otherboxes so that the boxes may be dischargedfrom the stack'in tiersof twoor-in; any other arrangement. desired. Although I have described theapparatuses removing boxes singly, it willbe understood that withequ-alfacility, t'heapparatus can remove more than one box from thebottom of a stack;

Haying thus. described my invention; and the presentpreferredembodiments thereof I desire toemphasize the fact that manymodifications may be resorted to in a manner, limited Only by a justinterpretation of the, followingv claims, wherein;

I-Iaying thusdescribed my invention; I claim:

1 ,Ir i a boxv unstacking apparatus, anunstacking station, a feedconveyor adapted to feed'boxes t o th e .unsllfi cking station, verticalguide members disposed at, each side, of the station, plates mounted-toinove up and down onthe guide memb,e 1:s, a chain, connected, at, oneside to each of the, platesa sprocket aboveeach plateand receivingachain, a crank, member at one side of each sprocket, each crank memberhaving a roller thereon, each chain passing one of the rollers, means toanchor the other end; of the cl ains, means to rotate the crank memberto raise and lower the plates, and a box supporting member mounted oneach plate; each box'supporting member. having a. box engagingpart'thereon adapted to engage beneath a box at the station;

2: In a box unstackingapparatus; an unstackiing .station-, afeedconveyor adapted tofeedboxes to ,the unstackingstation, verticalguide members disposed". at each, side of the station, plates mounted tomoveup and down'onthe guide membeILS. achain connectedat' one endto eachof. the plates, a sprocket above each plate and receiving a, chain acrank member at one side of each sprocket, each crank member having, aroller thereon each, chain passing over. one of the rollers, means, to,anchor the other end of'jthe chains; means to. rotate' the. crank,member' to raiseand. l wer the plates, a box supporting memher having abox engaging part thereon adapted to .engage beneath a box at thestation; andmeans to ve saidboxengasing p s p t to pe m delivery of a,stack of boxes tothe receiving sta ion.

3. VA, jbox unstacking mechanism including a frame, .a pair, of;substantially vertically extending, an le. shaped; b x. se ringmembers,e c m mb r har ngracesadap edt eneasethe front faceiandn he ndia e of. aa s pport r pivoted at its outer endfin ea ch 'of the securing memb r sid. arms, beingirearwardly directed; pivotei upp rtingmeans on the,frame ands m pbrfinafihe. inn r end'siofgr aid arms, a cam.-onerabletomove thesecuringmembers towardsthe ends of'boxes in a stack,andacam operableto movelsaid arms ,rearwardly against a. .box inhthe sack,

4,, A .box unstacking mechanism, including a frame, a backing plate,'means mounting the backing plate on the frame for transverse movement,in a substantially vert ical plane, a pair of substantially verticallyextending angle, shaped securing ,members, each member having facesadapted to engage the. front face and the end faceiof abox, aysupportingarm pivoted to each ofgthesecuring members for movement about ahorizontal" axis, said arm being upwardly and rearwardly inclined,universal supporting means on,. the,frameand supporting the inner endsof saidarmsta lever disposed. to bevrocked b'y the secondbox from thebottom of'a stack in the apparatus; cammeans operable by said lever tomove the securing members towards the-ends of boxes-in the stack, andother cammeans to move said arms downwardly'to movea box engagedby thearms rearwardly'against the backing plate.

5. A box unstacking mechanism including a frame; a backing plate, meansmounting the backing plate on the frame fortransverse movement in asubstantially vertical plane, a pair of substantially verticallyextending angle shaped securing members, each member having facesadapted to engage the front face and end face of a box, asupportingarmpivoted at its outer end on each of the securing members formovement: about a horizontal axis, said arms'being upwardly and;rearwardlyinclined and having bearingsattheir inner ends, saidbearingshaving their; axes substantially vertical, a horizontal shaft atthe, inner endof'said arms, each of said bearings" being rotatablymounted onthe horizontal shaft to provide a substantially universalmounting for the arms, a pivot rod extending downwardly through each ofthe first mentioned bearings, each pivot rod terminating at its lowerend in a boss, an extension armextending downwardly from each ofthe'second mentioned bearings, an angle member connecting said extensionarms, spacers on the connecting angle member, said bosses beingmountedon' said spacers, upwardly inclinedbraces each having one enden'- gaging a boss and rotatable with the pivot rod, the other end ofeach of said last mentioned braces being'connecte'd' to-one of thesupporting arms adjacent to the lower end of the latter, a leverdisposed to be rocked by the second box from the bottom of a stackin-the apparatus, cam means operable by said l'ever'togmove thesecuringmembers about the axis of thefirst mentionedbearings towardsthe boxes inthe stack, cam means to-move said arms about their horizontal axesdownwardl'yto cause'the facesof the supporting members whichengage thefront face of thebox to move an engaged box rearwardly against thebacking plate, and other cam means to move said arms towards each otherabout their vertical, pivots to engage and support the box.

6; A box unstacking mechanism includinga frame, a backing plate, meansmounting the backingplate on'the frame, for transverse movement in asubstantially vertical plane, a pair of substantially verticallyextending angle shaped securing; members, each member having facesadapted to engage the front faceand the endface of a-box; a Supportingarm pivoted at its outer end on each of the securing members for-move'-ment about a horizontal axis, said arms being upwardly and rearwardlyinclined and, having bearings at their inner-ends, saidbearingshaving-their axes substantially vertical, a horizontal shaft at theinner end of said arms, each of said bearings being rotatably mounted onthe horizontal shaft to provide a substantially universal mountingfor-the arms, an upwardly and rearwardlyinclined supportinggrod secured;to the upper end of each securing member, aboss on the frame, said bosshaving an aperture" through which said rodextends, resilientmeansnormally urging the rods rearwardly, a pivot rod extendingdownwardly through each ofthe-first mentioned bearings, each pivot rodterminating at its lower end in a boss, an extensionarmextendingidownwardly from each of the second mentionedbean ingshananglemember connectingsaid extension arms; spacers on the connectingangle'membei",

said bosses being mounted on said spacers, upwardly inclined braces,each having one end engaging a boss and rotatable with the pivot rod,the other end of each of said last mentioned braces being connected toone of the supporting arms adjacent to the lower end of the latter, alever disposed to be rocked by the second box from the bottom of a stackin the apparatus, cam means operable by said lever to move the securingmembers about the axis of the first mentioned bearings towards the boxesin the stack, cam means to move said arms about their horizontal axesdownwardly to cause the faces of the supporting members which engage thefront face of the box to move an engaged box rearwardly against thebacking plate, and cam means to move said arms towards each other abouttheir vertical pivots to engage and support the box.

'7. A box unstacker including a frame, a backing plate, support membersengaging the backing plate and frame and mounting the backing plate forlateral shifting movement in a substantially vertical plane, a pair ofspaced, substantially horizontal, parallel brace members, meanspivotally mounting the inner ends of each of the brace members to thebacking plate for movement about substantially vertical axes, and meanspivotally securing the forward end of each of said brace members to theframe for movement about substantially vertical axes.

8. A box unstacker including a frame, a pair of spaced depending arms,means pivotally mounting the arms on substantially horizontal pivots tothe frame, a backing plate, means pivotally mounting the lower ends ofsaid depending arms on the backing plate, a pair of upper, parallel,spaced, substantially horizontal brace members, means pivotally mountingthe inner ends of the brace members to the backing plate for movementabout substantially vertical axes, means pivotally securing the forwardend of said brace members to the frame for movement about substantiallyvertical axes, a pair of lower, substantially horizontal, parallel bracemembers, means pivotally connecting the inner ends of the lower pair ofbrace members to the backing plate for movement about substantiallyvertical axes, and means pivotally connecting the outer of the lowerpair of brace members to the frame for movement about substantiallyvertical axes.

9. In a box unstacking apparatus, box securing and holding meansincluding a frame, a backing plate, spaced parallel arms mounted on theframe and pivotally secured to the backing plate to permit lateralmovement of said backing plate, a pair of spaced shafts on the frame, apair of spaced arms, means pivotally mounting the arms on the shafts, abox gripping member pivoted on each shaft thereof, a cam operable tocause the gripping members to move towards each other to engage a box,and cam means to cause the gripping members to move towards said backingplate to move a box engaged by the gripping members against the backingplate.

10. A box unstacker including a frame, a horizontal cross member on theframe, a pair of spaced depending arms, means pivotally mounting thearms on substantially horizontal pivots to the cross member, a backingplate having a horizontally disposed stiffening member at its upper end,means pivotally mounting the lower ends of said depending arms on thestiffening member, a pair of upper, parallel, spaced, substantiallyhorizontal brace members, means pivotally mounting the inner ends of thebrace memhere on the stiffening member for movement about substantiallyvertical axes, the frame including forward extending upper members,means pivotally securing the forward end of said brace members on theupper frame member for movement about substantially vertical axes, apair of lower, substantially horizontal, parallel brace members, meanspivotally connecting the inner ends of the lower pair of brace membersto the backing plate for movement about substantially vertical axes andmeans pivotally connecting the outer of the lower pair of brace mem-'bers to the frame for movement about substantially vertical axes.

11. In a box unstacking apparatus, holding means, a lowerator movable toengage a box held by the holding means, said lowerator including spaced,opposed, vertical guide members, shafts mounted to move up and down onthe guide members, stack supporting arms journaled on said shafts, meansto cause said supporting arms to move inwardly and outwardly to engage abox of a stack, means to align the lowermost box in a stack prior tounstacking, said aligning means including pivoted aligning arms, andcams operable to move said aligning arms to box engaging position toalign a box in a stack.

12. In a box unstacking apparatus, holding means, means to cause saidholding means to engage and support a stack of boxes, a loweratormovable to engage a box held by the holding means, said loweratorincluding spaced, opposed, vertical guide members, plates mounted tomove up and down on the guide members, a chain connected at one end toeach of the plates, a sprocket above each plate and receiving a chain, acrank member at one side of each sprocket, each crank member having aroller thereon, each chain passing over one of the rollers, means toanchor the other ends of the chains, means to rotate the crank member toraise and lower the plates, means to release the holding means, adelivery conveyor, means to lower the lowerator until the box heldthereby is at a location adjacent to the delivery conveyor, means tocause the holding means to engage a box above the lowermost box of thestack being lowered by the lowerator when the lowermost box in the stackbeing lowered is at said location, and means to further lower thelowerator while the holding means holds the reduced stack to dispose thelowermost box of the stack being lowered onto the delivery conveyor.

13. In a box unstacking apparatus, holding means, a delivery conveyor, alowerator movable to engage a box held by the holding means, saidlowerator including spaced, opposed, vertical guide members, platesmounted to move up and down on the guide members, horizontal shaftssupported by each of said plates, a pair of spaced, upwardly inclinedstack supporting arms journaled on each of said shafts, a transversestack engaging member secured to the upper ends of each pair ofsupporting arms, means to cause said supporting arms to move inwardlyand outwardly to engage a box of a stack, means to align the lowermostbox in a stack prior to unstacking, said aligning means includingsubstantially vertically directed aligning arms pivotally arranged onsaid shafts intermediate said supporting arms, a box engaging andaligning member secured to the upper end of each of said aligning arms,cams operable to move said aligning arms to box engaging position toalign a box in a stack, a chain connected at one end of each of saidplates,

azspmeket aboveeeach: plate-and; adapted, to receive:a chain, a! crankmember: at one.- side, oi, andirotatable:with-,; each sprocket, eachcrank member having-a roller: thereon, reach-chain passing over-one,ofthe rollers, means to fixedly anohorqthe other endrof the-chains;means tomove the: holding; means to; releasing position, andmeansytoizrotate the-crankto lower the lowerator untili the box; heldthereby is at; a; location ad- J'aeent. to; the; delivery conveyor.-

14. In--- a.- box"; unstacking; apparatus, holding means; means-tocause: said? holding, means to en ageandrholda'stacleof boxes,aidelivery GOD-r veyor, a lowerator movable to engage-a box. held by;theholding; means, saidilowerator including spaced oppose d; vertical;guide. members, plates nmunteditomovenp andldownpn theguidememhers;,horizontaishaftsr supported: by each of: said platesgapair; ofspaced-1 upwardlv directed; stack supporting arms; journaled on each;sidesof said shafts; a transverse stackengaging memberrcone meeting -theupper endsof; each:pair of supporting arms; means; to cause saidsupporting, arms to move-inwardly and outwardly; to; engage a boxofrasstack; means to;align'-,the lowermost-box in azstackprior tounstacking said aligning means including substantially vertically:directed align.- ing arms; pivotally, arranged on said. shaftsintermediate saidsupportingarms, abox engaging and aligning; membersecured: to: the upper end 116 of said. arms, cams operable. to movesaid aligning arms to box engaging position to align abox in-.a stack,,achainlconneoted at, one. end ofweach of said, plates, asprocket aboveeach plate and adapted to receive a chain, a crank member at onefsideof, and rotatablewith, each. sprocket, each: crank member havingaroller, thereon, each chain passing over one ofv the rollers, means, tofixedly anchor the other endof the chains, means to move thev holding,means to, releasing position, and means. to rotate the crank ,to, lowerthe lowerator until thebox held thereby is at. a location adjacentto-the delivery conveyor.

AMBROSE A.. NEJA.

REFERENCES CITED The following; references are; of record; in the fileof thispatent:

UNITED STATES PATENTS Germany Apr. 11, 1927

